Whenever a starter goes out, his replacement needs to step right in and keep things rolling.

This time, that next man up is defensive coordinator Jack Del Rio, who’s in charge of the Denver Broncos while their head coach recovers from heart surgery.

While Del Rio was running his first practice as the Broncos interim coach Monday, Fox was in the recovery room at Carolinas HeathCare System’s Sanger Heart & Vascular Institute in Charlotte, N.C., after having his aortic valve replaced in an operation he had hoped to delay until after the Super Bowl.

“We all wish him a speedy recovery. The best way that we could honor him is to go out and play great football,” Del Rio said after taking over a 7-1 team that’s the prohibitive Super Bowl favorite even though the Broncos trail the unbeaten Kansas City Chiefs (9-0) in their own division.

Fox’s wife, Robin, issued a statement through the team that said Fox’s operation went well and he was being monitored in the hospital’s post-operative critical care unit.

“Along with his medical team, we will take great care of him so he can fully recover and get back to coaching the Broncos as soon as possible,” she said.

Del Rio, who spent nearly nine seasons as Jacksonville’s head coach before joining Fox’s staff last year, said he’s honored to serve as caretaker of Fox’s team.

“We’re on a mission to carry on and continue the things that Coach Fox has instilled and started with this football team,” Del Rio said. “This is Coach Fox’s team. I’m merely the person that’s able to keep it running right now while he’s healing.”

Players aren’t expecting any change with Del Rio in charge, either — OK, maybe a scowl here or a tongue-lashing there, but nothing substantively different.

“Nothing changes,” wide receiver Bubba Caldwell said. “It’s just a different co-pilot. It’s just a different guy saying the same words.”

Fox’s health scare is the latest blow to a team that’s faced one road block after another. Elvis Dumervil left via a fax foul-up. All-Pro linebacker Von Miller tried to game the NFL drug-testing system. Two team executives were suspended following drunken driving arrests. And Ryan Clady, Peyton Manning’s blindside protector, lasted just two games after signing a $57.5 million contract.

Still, the Broncos are averaging 43 points a game. So, it’s easy to see why Executive Vice President John Elway isn’t bemoaning his team’s run of misfortune.

“No, because I think we’ve got a good football team. For us to get where we want to go we’re going to have a bunch more bumps, too,” Elway said. “I think you learn from each bump. It makes you tougher. It makes us tougher as an organization. It makes us tough as a team and all that can do is help us. …

“I think the best thing is this is good for John Fox in the fact that he’s going to be able to get healthy and we’ll continue this thing on the tracks until he gets back.”

Fox is expected to miss several weeks while recovering from the open-chest surgery and undergoing arduous cardiac rehabilitation.

Elway said he reached out to Indianapolis general manager Ryan Grigson to learn how the Colts dealt with head coach Chuck Pagano’s leukemia fight last year. Assistant Bruce Arians stepped in for Pagano and presided over one of the greatest turnarounds in NFL history.

Del Rio said he plans to reach out to Arians, now coach of the Arizona Cardinals, “and pick his brain a little bit on that.”

What he won’t have to do is search for Fox’s blueprint.Like Fox, Del Rio’s roots are on the defensive side of the ball. This is his 17th season coaching in the NFL following an 11-year playing career. That includes eight-plus seasons as head coach in Jacksonville, where he was 69-73, including 1-2 in the playoffs from 2003-11.

He rejoined Fox’s staff in Denver last year after serving as his defensive coordinator in Carolina in 2002.

Fox was hoping to put off the operation until the offseason but after meeting with his cardiologist in Raleigh, N.C., late last week, he began feeling dizzy while playing golf near his offseason home in Charlotte on Saturday and was hospitalized.

Fox is expected to remain in the hospital at least until the weekend and he might be able to do his rehab in Denver. He won’t be able to do any heavy lifting for 10 weeks.

It’s uncertain when he’ll be well enough to consult with Del Rio on football matters, however.

“The doctors are going to tell us the right thing to do there,” Elway said. “I think again, the concern is going to be with John’s health, not only for this season, but John’s health for the rest of his life. I feel like we’re in really good hands with Jack.”

Del Rio will maintain his duties as defensive coordinator. He noted that he called the defense while in Jacksonville, so pulling double duty is nothing new.

“The biggest thing is that you just don’t have the ability to turn your back to the field and coach your guys on the sideline,” Del Rio said. “So you lean on your staff to do that.”

He also stressed that every player will have to pick up the slack.

Del Rio has long commanded the respect of his players, who appreciate his resume as a star NFL linebacker. He’s a lot like Fox in that he’s considered a player’s coach, one who understands things from their perspective.

They have similar philosophies, backgrounds and approaches, and while some differences might emerge in his game-day decisions, “Jack Del Rio knows John Fox better than anybody,” Elway said. “He’s coached under him and so I think that he’ll continue this train on the tracks that we’re on.”

One they believe will lead to the Super Bowl on Feb. 2, by which time Fox should be able to lift seven pounds, the weight of the Lombardi Trophy.